Fire-door smoke preventer



A. P. HARDER AND A. 0. OLSON. FIRE DOOR'SMOKE PREVENTER. APPLICATION FILED OCT. 22. I919 1,431,949, Patented Oct. 17, 1922 Patented Got. it, 1922.

ALEXANDER P. HARDER AND ALBERT 0. OLSON, 0F ROCKFORD, ILLINOIS.

rntnnoon SMOKE ranvnnrsn,

Application 'filed' October 27, 1919. Serial No. 333,7;3.

To all whom it may concern:

Be it known that we, ALEXANDER P. HARDER and ALBERT U. @LsoN, citizens of the United States, residing at Rockford, in the county of W'innebago and State of Illinois, have invented certain new and use ful Improvements in. Fire-Door Smoke Prevcntcrs, of Which the following is a specification.

This invention has reference in general to stoves and furnaces, and more particularly to hot air furnacesand to other kinds of heaters having front lire doors.

These furnaces are now generally used in heating homes, and it is desirable that they shall be operated in suchmanner as not to interfere with sanitary and hygienic conditions. Such furnaces, however, invariably permit the escape of gas, smoke and fumes through the fire door opening when this door is opened for replenishing the fuel supply, especially when soft coal is used. This escape of smoke and fumes is, of course, very objectionable, and we have aimed in the present invention to eliminate this smoke nuisance in a very effective and satisfactory manner.

To this end our invention contemplates the provision of a hood. structure arranged in a novel manner in front of a heater above the fire door, the hood having a passage adapted to convey the smoke and fumes escaping through the fire door opening, into the interior of the heater and preferably to the flue outlet; and further providesa closure in said passage adapted to be opened and closed by and through similar-movements of the [ire-door. That is, we have provided a novel means by which a line outlet passage opened by opening the fire-door, whereupon smoke and fumes escaping through the fire-door will be carried away through said passage, and upon closing the fire-door the passage will be likewise closed so as not to interfere with normal operation of the furnace.

Still another object is to provide improvements of the character descrioed, which shall be constructed in such simple manner as to be thoroughly practical and for the purpose in mind and shall be capable of economical production.

Other objects and attendant advantages will be appreciated as the invention becomes better understood by reference to the follow ing description when considered in connection with the accompanying drawings, in which- Figure 1 is a fragmentary front view of a furnace equipped with our improvements;

Fig. 2, a fragmentary horizontal section taken substantially on the line 2-2 of Fig. 1, showing the lire-door open; and

Figs. 8 and l, fragmentary vertical sectional views taken substantially on the line 33 of Fig. 1, showing respectively the fire-door closed and open.

Our improvements as will be presently understood, are adapted for use in connection with any kind of furnace or heater having a front lire-door leading to the fire pot. In the present case, we have shown simply for purpose of illustration our improvements in connection with a hot air furnace of the circular radiating drum type. The drawing illustrates the furnace somewhat diagrammatically and only such parts are shown as are necessary for an understanding of the present invention. The well known parts consists of a fire pot 5 opening at its top into a circular radiating drum 6, which communicates with the flue outlet as is well understood in this art. A suitable casing 7 incloses the fire pot radiating drum and is faced as usual in furnaces of this type with. a face plate 8. Through this face plate is attire pot opening 9 communicating with the fire pot and adapted to be closed by a fire-door 11 hingedly supported to swing outwardly to an open position in the usual manner. In a furnace of the construction thus far described, fumes, smoke and gas invariably escape from the combustion chamber through the opening 1) when the door ill is opened. This nuisance is especially aggravating when soft coal is used, and in some instances the escape of a considerable volume has a dangerous effect.

In the present invention, we have provided means for conducting the escaping smoke and fumes into the interior of the heater by means of a bypass, and preferably to a conduit leading to the flue outlet, and in order to insure uniform and positive results, we have provided a passage which shall be automatically opened instantly upon and by opening the fire-door so that the ris- 7 mg fumes will pass directly into the furnace and shall be closed by similar movements of the fire-door so as not to interfere with normal functioning of the heater. This is obtained in the present instance by the provision of a hood structure providing a wide open-mouth passage directly overlying the top of the fire-door opening and leading upwardly and into the circular drum which leads to the flue outlet. For convenience and simplicity in manufacture and assembling, this hood structure is made in two sections, viz a base 12 and a cap 13. This base member, rigidly secured to the face plate 8, reaches out a canopy or hood over the top of the fire-door and affords a relatively long opening extending substantially beyond the sides of the lire-door, of sufficient area to catch all of the smoke and 1 gas escaping through the opening 9 when. the

fire door is opened. These gases pass upwardly through an elongated opening 14: in the top wall of the base section 12 and are guided by the cap inclosure 13 through an opening 15 in the face plate 8 and thence through a passage 16 into the passages of the circular radiating drum. The cap section 18 is removably seated on the base section 12 so as to afford ready access to the interior of the furnace for cleaning and other purposes. It is necessary that the opening 14.- shall normally be closed, but opened only When the fire-door 11 is opened. For this purpose, we have provided a gate or 010- sure 17 pivotally mounted at 18 and equipped with a projecting arm 19 adapted to be actuated by opening and closing movements of the door 11 to similarly move the closure 17. As shown in Fig. 3, the arm 19 F rests on top of the door 11 when the latter is closed, thereby holding the gate 17 in closed position. Upon swinging the door 11 open, the arm 19 will instantly drop behind the door to the position shown in Fig. 4. The escaping smoke and fumes will rise upwardly and be conveyed and drawn through the hood structure above described, back into the, heater and through suitable passages to the flue outlet. Upon closing the fire-door, it will strike the projecting arm 19 and swing it and the gate 17 up wardly to closed position, in which such parts will be held by the fire-door in the manner shown in Fig. 3. It will thus be seen that themattei ofopening and closing the by-pass leading back to the heater, is automatically effected. and requires no attention on the part ofthe attendant.

From the foregoing, it will be manifest that the smoke nuisance and undesirable effects from opening a lire-door and from replenishing the coal supply are entirely 0bviated by our present improvements. Furthermore, the desired results are positively assured by reason of the fact that opening and closing of the passage to the flue outlet is automatically effected and the attention of the operator is not required in this regard. It will alsobe manifest that our improvements in their present form consist of but very few parts and shaped in such manner that they'may be produced and assembled at a very low cost.

It is believed that the foregoing conveys a clear understanding of the principles and objects of our invention, and while we have illustrated and described but a single Working embodiment, it should be understood that various changes might be made in the construction and arrangement Without departing from the spirit and scope of the invention as expressed in the appended claim, in which- We claim: v

In a heater, a front plate having a firedoor opening and a by-pass opening time above, communicating with the flue outlet, a fire-door, and a hood structure providing a passage leading from the top of the the door to said by-pass opening, said hood structure comprising a base section open at the bottom and having a top wall provided with a restricted opening, a cap section resting upon the base section and providing a closed passage between said opening in the top of the base section and said by-pass opening, and a gate for opening and closing said opening in-the top of the base section.

ALEXANDER r. HARDER. ALBERT o. oLsoN. 

